Term: Distortion

Distortion simply means “altering.” In audio, distortion implies a change that adds unwanted harmonics or noise to a signal. Guitar amp distortion is desirable while mic preamp distortion is usually undesirable. Common types of distortion include clipping, frequency distortion, intermodulation distortion, transient intermodulation distortion, and phase distortion. All these types of distortion are usually combined and referred to as total harmonic distortion (THD), which is expressed as a percent.